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1.
The localization of neuropeptide Y (NPY) and atrial natriuretic peptide (ANP) in the endothelial cells of human umbilical blood vessels was studied using the pre-embedding peroxidase-antiperoxidase (PAP) technique for electron microscopy and avidin-biotin-complex (ABC) immunostaining for endothelial cells cultured from umbilical vein. Subpopulations of NPY- and ANP-immunoreactive endothelial cells were present in term umbilical vein and artery. The umbilical vein contained more positive cells than the artery. The percentage of NPY- and ANP-immunoreactive umbilical vein cells in culture was 32% and 44%, respectively, out of a total of 3013 cells examined. The possibility that these potent vasoactive substances located in the endothelial cells of the non-innervated umbilical vessels are involved in the local regulation of blood flow is discussed.  相似文献   
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目的:研究脐血管前置产前超声表现及临床效果。方法:回顾性分析2017年1月至2018年12月期间本院收治的34例脐血管前置孕妇临床资料,均进行产前超声检查,将结果与产后病理结果进行比较,分析超声表现。结果:同产后病理检查结果相比较,34例孕妇的产前超声诊断准确率、误诊率分别为97.06%、2.94%,数据对比差异无统计学意义(P>0.05),产前超声检查显示的胎盘及脐带入口情况主要为帆状胎盘、脐带胎盘边缘附着、边缘性前置胎盘、低置性前置胎盘、副胎盘等。结论:产前超声检查具有较高的脐血管前置诊断准确率,可为临床分娩结局的改善提供指导,适合推广应用在临床中。  相似文献   
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Coronavirus disease-2019 (COVID-19) has affected more than 200 countries worldwide. This disease has hugely affected healthcare systems as well as the economy to an extent never seen before. To date, COVID-19 infection has led to about 165000 deaths in 150 countries. At present, there is no specific drug or efficient treatment for this disease. In this analysis based on evidential relationships of the biological characteristics of MSCs, especially umbilical cord (UC)-derived MSCs as well as the first clinical trial using MSCs for COVID-19 treatment, we discuss the use of UC-MSCs to improve the symptoms of COVID-19 in patients.  相似文献   
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摘要 目的:分析脐带间充质干细胞对卵巢早衰家兔的治疗效果及机制研究。方法:经腹腔连续注射 2 d 环磷酰胺50 mg/(kg?d)建立卵巢早衰家兔模型。将建模成功的10只家兔随机分成模型组和治疗组,每组5只。建模一周后,治疗组家兔每天经耳缘静脉注射5×106/mL脐带间充质干细胞混悬液2 mL,连续注射3 d。模型组家兔经耳缘静脉注射等量无菌生理盐水。于治疗后 0 d、7 d、14 d和28 d,取家兔静脉血检查血清激素表达水平。于治疗后28 d,检测家兔卵巢中生长卵泡数、封闭卵泡数、黄体数、富半胱氨酸蛋白61(CYR61)和结缔组织生长因子(CTGF)mRNA及蛋白质相对表达量。结果:治疗前,模型组和治疗组家兔血清雌二醇(E2)、促卵泡生成素(FSH)、FSH/黄体生成素(LH)、抑制素B(INHB)和抗苗勒管激素(AMH)、均无显著差异(P>0.05)。与模型组相比,治疗后治疗组家兔血清E2和INHB水平显著上升(P<0.05),FSH水平显著下降(P<0.05),FSH/LH均无显著差异(P>0.05)。随着治疗时间延长,治疗组家兔血清E2和FSH水平周期性波动。治疗28 d后,与模型组相比,治疗组家兔血清AMH水平显著升高(P<0.05);卵巢组织中CYR61和CTGF mRNA及蛋白质相对表达量均显著升高(P<0.05);生长卵泡数显著升高(P<0.05);封闭卵泡数和黄体数均显著降低(P<0.05)。结论:静脉注射脐带间充质干细胞可通过上调CYR61和CTGF的表达,促进卵泡生成,恢复卵巢功能,达到治疗卵巢早衰的临床效应。  相似文献   
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Abstract

Objective: Multiple pregnancy is associated with an enhanced metabolism and demand for O2, which may lead to the overproduction of reactive oxygen species and the development of oxidative stress. The degree of oxidative damage depends on the level of the antioxidant protection system of the foetus. The objective of the study was to identify the relationship between the state of the maturity and the antioxidant status of twin neonates. Investigations of the umbilical cord blood were carried out to detect differences in the antioxidant defence system between mature and premature twin neonates.

Methods: The activities of the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) enzymes, the levels of reduced glutathione (GSH), protein carbonyls and oxidized lipids and the total antioxidant capacity of the plasma were determined.

Results: The level of lipid peroxidation was significantly higher in the premature neonates. An increase in the total antioxidant capacity was accompanied by a decrease in the damaged protein concentration. Significantly elevated activities of GPx alone were observed in the premature twins, though the GSH content too tended to be increased. The activity of SOD was decreased in the premature neonates.

Discussion: The antioxidant status of twin neonates are mainly influenced by maturity. We suggest that the level of lipid peroxidation might be of clinical value as a marker of pre- and perinatal distress in twins.  相似文献   
7.
Stem cells have been considered as possible therapeutic vehicles for different health related problems such as cardiovascular and neurodegenerative diseases and cancer. Secreted molecules are key mediators in cell–cell interactions and influence the cross talk with the surrounding tissues. There is strong evidence supporting that crucial cellular functions such as proliferation, differentiation, communication and migration are strictly regulated from the cell secretome. The investigation of stem cell secretome is accumulating continuously increasing interest given the potential use of these cells in regenerative medicine. The scope of the review is to report the main findings from the investigation of stem cell secretome by the use of contemporary proteomics methods and discuss the current status of research in the field. This article is part of a Special Issue entitled: An Updated Secretome.  相似文献   
8.
目的:探讨脐带间充质干细胞移植联合表皮生长因子治疗III、Ⅳ期压疮的临床效果。方法:选取我院2011-2012年收治的III、Ⅳ期压疮患者143例为研究对象,随机分为对照组、实验一组和实验二组。对照组30例压疮患者行常规换药,实验一组58例压疮患者应用脐带间充质干细胞移植联合表皮生长因子治疗,实验二组55例压疮患者仅应用表皮生长因子治疗。治疗后,比较三组患者愈合时间及愈合效果。结果:实验一组和实验二组的显效时间和愈合时间均较对照组显著缩短,且实验一组的显效时间和愈合时间较实验二组更短,差异均有统计学意义(均P〈0.05)。实验一组的治愈率显著高于对照组(P〈0.05),而与实验二组比较无统计学差异(P〉0.05),实验二组的治愈率与对照组比较无统计学差异(P〈0.05)。实验一组的总有效率显著高于对照组和实验二组(P〈0.05),而实验二组的总有效率与对照组比较无统计学差异(P〉0.05)。结论:脐带间充质干细胞移植联合表皮生长因子较单用表皮生长因子及常规治疗方法更好的改善III、Ⅳ期压疮创面的愈合,避免患者组织感染,提高压疮患者的生活质量。  相似文献   
9.
Co-expression of dopamine β-hydroxylase (DβH) and neuropeptide Y (NPY) has never been examined in ovary (OV) and umbilical cord (UC) of the European bison (Eb), the endangered wild species. The OV and UC samples were harvested from seasonally eliminated Eb females (45–120 days post coitum). Frozen histological sections were examined by double fluorescent immunohistochemistry (dF-IHC), using the primary mouse anti-DβH monoclonals and rabbit anti-NPY polyclonals and then the immunocomplexes were visualized with FITC and CY3 fluorophores, respectively. Numerous DβH immunoreactive nerve fibers (DβH-IRs) and a little less frequent NPY-IRs were found in the bundle-like structures, innervating mainly perivascular regions of the OV. The NPY-IRs constantly co-expressed DβH, while some DβH-IRs did not express NPY. This specific pattern of innervation was observed both in the stromal and cortical regions of the OV. The simultaneous co-expression of DβH and NPY were also detected in the UC, in which specific single or bundle-like structures ran along the smooth muscles of blood vessels. The spatial-specific co-expression of DβH and NPY in OV and UC, may suggest that these markers are involved in the control of vascularization that regulates nourishing blood circulation required for proper pregnancy maintenance and efficient embryo/fetus development in the Eb.  相似文献   
10.
Human umbilical cord mesenchymal stem cells (hUCMSCs) are considered to be an ideal replacement for bone marrow MSCs. However, up to date, there is no convenient and efficient method for hUCMSC isolation and culture. The present study was carried out to explore the modified enzyme digestion for hUCMSC in vitro. Conventional enzyme digestion, modified enzyme digestion, and tissue explant were used on hUCMSCs to compare their efficiencies of isolation and culture, to observe primary cell growth and cell subculture. The results show that the cells cultured using the tissue explant method had a longer culture cycle (P < 0.01) and lower yield of primary cells per centimetre of umbilical cord (P < 0.01) compared with the two enzyme digestion methods. Subculture adherence and cell doubling took significantly less time with the tissue explant method (P < 0.05) than with the conventional enzyme digestion method; however, there was no significant difference between the tissue explant method and the modified enzyme digestion method (P > 0.05). Comparing two enzyme digestion methods, the modified method yielded more cells than did the conventional method (P < 0.01), and primary cell adherence took significantly less time with the modified method than with the conventional method (P < 0.05). Cell cycle analysis of the third-generation hUCMSCs cultured by modified enzyme digestion method indicated that most cells were quiescent. Immunofluorescence staining showed that these cells expressed MSC markers CD44 and CD90. And Von Kossa and oil red O staining detection showed that they could be differentiated into osteoblasts and adipocytes with induction medium in vitro. This study suggests that hUCMSC isolation and culture using 0.2 % collagenase II at 37 °C for digestion of 16–20 h is an effective and simple modified enzyme digestion method.  相似文献   
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